Amazingly, this module didn't have a unit test yet.
Change-Id: I021bb83cc747174196958db14c97154f0574c2e8
Reviewed-on: https://boringssl-review.googlesource.com/32111
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>